text: /* Copyright (C) 1994 Free Software Foundation, Inc.
  This file is part of the GNU C Library.
  
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2, or (at your option)
  any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  
  /*
   * My personal strstr() implementation that beats most other algorithms.
   * Until someone tells me otherwise, I assume that this is the
   * fastest implementation of strstr() in C.
   * I deliberately chose not to comment it.  You should have at least
   * as much fun trying to understand it, as I had to write it :-).
   *
   * Stephen R. van den Berg, berg@pool.informatik.rwth-aachen.de	*/
  
  #include <string.h>
  #include <sys/types.h>
  
  typedef unsigned chartype;
  
  char *
  strstr (phaystack, pneedle)
       const char *phaystack;
       const char *pneedle;
  {
    register const unsigned char *haystack, *needle;
    register chartype b, c;
  
    haystack = (const unsigned char *) phaystack;
    needle = (const unsigned char *) pneedle;
  
    b = *needle;
    if (b != '\0')
      {
        haystack--;				/* possible ANSI violation */
        do
  	{
  	  c = *++haystack;
  	  if (c == '\0')
  	    goto ret0;
  	}
        while (c != b);
  
        c = *++needle;
        if (c == '\0')
  	goto foundneedle;
        ++needle;
        goto jin;
  
        for (;;)
          {
            register chartype a;
  	  register const unsigned char *rhaystack, *rneedle;
  
  	  do
  	    {
  	      a = *++haystack;
  	      if (a == '\0')
  		goto ret0;
  	      if (a == b)
  		break;
  	      a = *++haystack;
  	      if (a == '\0')
  		goto ret0;
  shloop:	    }
            while (a != b);
  
  jin:	  a = *++haystack;
  	  if (a == '\0')
  	    goto ret0;
  
  	  if (a != c)
  	    goto shloop;
  
  	  rhaystack = haystack-- + 1;
  	  rneedle = needle;
  	  a = *rneedle;
  
  	  if (*rhaystack == a)
  	    do
  	      {
  		if (a == '\0')
  		  goto foundneedle;
  		++rhaystack;
  		a = *++needle;
  		if (*rhaystack != a)
  		  break;
  		if (a == '\0')
  		  goto foundneedle;
  		++rhaystack;
  		a = *++needle;
  	      }
  	    while (*rhaystack == a);
  
  	  needle = rneedle;		   /* took the register-poor aproach */
  
  	  if (a == '\0')
  	    break;
          }
      }
  foundneedle:
    return (char*) haystack;
  ret0:
    return 0;
  }
  